1. Field of the Invention
This invention relates to telecommunication methods and apparatus. More specifically, this invention relates to methods and apparatus for the use of telephone key pads for inputting alphabetic information.
2. Description of the Prior Art
Telephone keypads are known in the prior art (see FIG. 1). Telephone keypads have numerical keys numbered from 0 to 9, a star key, and a "#" (pound or hash or number) key. The original purpose of telephone keypads was to input the ten digits of the decimal number system into the telephone system for purposes of calling telephone numbers. Because the telephone keypad is limited to the twelve indicated keys, which are marked in the well known manner shown in FIG. 1, these keypads do not readily lend themselves to the input of the alphabet, with twenty six characters (or any other alphabet), as would a conventional alphabetic keyboard for a typewriter or word processor.
In the conventional telephone keypad, the "1" button has no letters on it. The "2" button is marked with the letters "ABC", and so forth through the "9" button, all marked in a well known manner. The "0" button is marked with "OPER" for the operator. The "*" button and the "#" button are marked only with "*" and "#", respectively.
From time to time in the use of the telephone instrument, it would be useful to input letters of the alphabet to provide alphabetic information, for example, to spell a person's name using the telephone keypad. There is no easy way to do this in the prior art, and this is a long felt frustrated need in the telecommunications industry. In theory, a number of dedicated buttons, one for each letter of the alphabet, could be added to a telephone instrument, in much the same manner as a typewriter, word processor or computer keyboard. However, in practice this is prohibitively expensive. Another solution is needed.